The present invention concerns umbrellas, more particularly collapsible umbrellas.
Collapsible temporary shelters, such as umbrellas and canopies, are well known. Conventionally, an umbrella is used to protect a user against the effects of snow, rain, sun and such, and consists of a canopy supported by a collapsible frame that is mounted on a central shaft. While this simple device is quick to deploy and provides shelter for the user, it suffers from a number of drawbacks. When the conventional umbrella is deployed, the canopy sweeps out a relatively large area before achieving its fully opened sheltering configuration. Disadvantageously, objects located near the umbrella may need to be moved or they may impede the umbrellas"" deployment. Also, a user, who may be lying or sitting beside the umbrella, for example sunbathing, who becomes desirous of shade, must move away from the umbrella to deploy it.
A few designs for collapsible umbrellas exist, including:
U.S. Pat. No. 6,273,111 issued Aug. 14, 2001 to D. Weiss and S. Peace for xe2x80x9cRetractable Umbrellaxe2x80x9d.
U.S. Pat. No. 5,690,131 issued Nov. 25, 1997 to B. Voigt, for xe2x80x9cUmbrellaxe2x80x9d.
U.S. Pat. No. 5,188,137 issued Feb. 23, 1993 to A. F. Simonelli for xe2x80x9cUmbrellaxe2x80x9d.
These umbrellas, however, suffer from a number of important disadvantages. Each is of a complicated design having many moving parts, which may be prone to jamming. Disadvantageously, the canopy is drawn into the central shaft by a series of flexible, lightweight ribs, which the user collapses. The collapsible ribs, when in an open configuration, may be prone to undesired inversion by sudden gusts of wind. In addition, the collapsible ribs do not appear to be sufficiently reinforced to be self supporting and may frictionally contact the canopy causing damage after prolonged use. Furthermore, the low reinforcement may also limit the size of the area to be covered by the canopy.
Thus there is a need for an improved collapsible umbrella.
The present invention is directed towards such a solution.
A portable, collapsible umbrella of the present invention provides a novel tensioning system, which includes a number of rigid or resilient curved rods and a number of longitudinally resilient cables, which operate in combination with the umbrella rib weight to allow a bottom up method of canopy deployment. In addition, the combination helps to stabilize the open umbrella canopy and to reduce canopy inversion. The novel tensioning system also increases the size of area covered by the canopy by maintaining a strong holding force on the deployed canopy. The bottom up method of deployment enables a user to open the umbrella without temporarily obstructing the area immediately around the umbrella or knocking over objects in the immediate area around the umbrella. Also, the bottom up method enables the user to open umbrella while in a supine position. The umbrella is inexpensive to manufacture, simple to operate, strong, yet lightweight and portable thereby allowing the user to set up the umbrella quickly and to move the umbrella to other areas when required. The umbrella is adaptable to include side panels or drapes which can be attached to the canopy to provide shelter from strong wind or blowing materials such as sand on a beach. The novel tensioning system may also be adapted to provide temporary shelter to cars, to a temporary aid stations mounted alongside a vehicle, to boats or to a small portable protected-observatory for a hunter or a birdwatcher.
In a first aspect of the present invention, there is provided a collapsible umbrella having a rib connector slidably mounted on a central shaft, a plurality of umbrella ribs, each rib having a first rib end portion and a second rib end portion, the first rib end portion being movably connected to the rib connector, and a flexible canopy covering the ribs, the umbrella comprises:
a resilient rib tensioning member connected to an end portion of the central shaft, the rib tensioning member being interconnected with the first rib end portion and the second end portion, such that:
i) in response to a first moving force against the rib connector, the rib connector moves from a default position to a first open position, the default position being when the umbrella is collapsed, the ribs lying generally adjacent the central shaft, the rib connector being positioned towards a mounting surface and away from the tensioning member, the second rib end portion being positioned towards the rib tensioning member, the first open position being when the second rib end portion is positioned away from the rib tensioning member, the rib connector being positioned away from the mounting surface, the rib tensioning member exerting a first threshold holding force on the second rib end portion;
ii) in response to a second moving force against the rib connector, the rib connector moves from the first open position to a second open position, the second moving force being greater than the first moving force, the second open position being when the rib connector and the second rib end portion lie along a plane generally horizontal to the mounting surface, the rib tensioning member exerting a second threshold holding force on the second rib end portion, the second threshold holding force being greater than the first threshold holding force;
iii) in response to a third moving force against the rib connector, the rib connector moves from the second open position to a third open position, the third moving force being greater than the second moving force and the second threshold holding force, the third open position being when the second rib end portion is inclined generally away from the generally horizontal line towards the mounting surface, the rib connector being moved towards the rib tensioning member, the rib tensioning member exerting a third threshold holding force on the second rib end portion, the third threshold holding force being less than the second threshold holding force, the ribs having a rib weight sufficient to bias the second rib end portions towards the mounting surface.
In a further aspect, in response to a fourth moving force against the rib connector, the rib connector moves from the third position to the default position, the fourth moving force being sufficient to overcome the rib weight biasing, the rib tensioning member having sufficient resilient force to pull the ribs into the default position.
Typically, the resilient rib tensioning member comprises: a plurality of generally curved rods extending outwardly from the shaft end portion; and a plurality of cables connected to the rib connector and the second rib end portion, the cables being movably connected to the curved rods.
Typically, each curved rod includes a rod end portion directed away from a shaft axis.
Typically, the resilient rib tensioning member further comprises a guide system connected thereto. The guide system comprises a plurality of hoops attached to an underside of each of the rods. In one aspect, the guide member includes three hoops.
Typically, the hoops are sized to allow the cables to pass therethrough.
Typically, the curved rods are rigid. In one aspect, the curved rods are resilient.
Typically, the cables are longitudinally resilient.
Typically, the rib connector is a cylindrical collar having an axial bore of sufficient size to slide over the shaft.
Typically, a plurality of anchoring members are connected to an outer collar wall. Each rib is hingeably connected to the anchoring member.
Typically, the cylindrical collar includes a plurality of cable connector hoops extending upwardly therefrom for connecting each cable thereto. Other objects and advantages of the present invention will become apparent from a careful reading of the detailed description provided herein, with appropriate reference to the accompanying drawings.